class PaymentSystem
  class << self

    def get_coupon(coupon_id)
      Stripe::Coupon.retrieve coupon_id
    end

    def get_plan(plan_id)
      Stripe::Plan.retrieve plan_id
    end

    def get_subscription(sub_id)
      Stripe::Subscription.retrieve sub_id
    end

    def get_customer(customer_id)
      Stripe::Customer.retrieve customer_id
    end

    def update_customer(customer, data)
      customer.source = data[:source]
      customer.save
    end

    def delete_customer(customer)
      customer.delete
    end

    def get_invoices(customer_id)
      Stripe::Invoice.list customer: customer_id
    end

    def create_customer(data)
      Stripe::Customer.create data
    end

    def create_subscription(customer, data)
      customer.subscriptions.create data
    end
    def end_subscription(subscription)
      subscription.delete at_period_end: true
    end

    def validate_plan_and_coupon(plan_id, coupon_id)
      plan = get_plan plan_id
      subscription_data = {
        plan: plan.id
      }
      if coupon_id.present?
        coupon = get_coupon coupon_id
        subscription_data[:coupon] = coupon.id unless !coupon.valid
      end
      subscription_data
    end

  end
end